Photoelectric conversion element and method for manufacturing the same

ABSTRACT

The purpose of the invention is to provide a photoelectric conversion element enable to ensure the connection of the contact electrode easily and accurately. 
     The plurality of the laser oscillator in which a semiconductor layer and the p-side electrode are laminated are formed on the same substrate. Each contact electrode formed on the base substrate through each opening of the insulating layer is electrically connected to each p-side electrode. Each opening corresponding to each laser oscillator placed side by side is formed in a staggered configuration in the alignment direction. Each contact electrode is extended in parallel with the alignment direction corresponding to each opening. Accordingly, the space between each opening and the space between each contact electrode which are placed side by side in the alignment direction are widened and the requirement for highly accurate position matching is eliminated. Therefore, each p-side electrode and each contact electrode can be connected easily and accurately.

STATEMENT OF CROSS RELATED APPLICATIONS

This application is a divisional application, and claims the benefit ofthe earlier filing date, of U.S. Ser. No. 09/306,183 (filed May 6, 1999)now U.S. Pat. No. 6,310,381 (now allowed), which claims priority toJapanese Application No. P10-126527, filed May 8, 1998; the disclosuresof which are incorporated by reference herein to the extent permissibleby law.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a photoelectric conversion elementhaving a contact electrode for a photoelectric conversion portions and amethod for manufacturing the same. More particularly, the inventionrelates to a photoelectric conversion element with the plurality ofphotoelectric conversion portions on the same substrate and a method ofmanufacturing the same.

2. Description of the Related Art

Today, different kinds of apparatuses such as an optical disc device, alaser beam printer, a duplicator using a laser diode, LD, have beendeveloped. In recent years, more rapidity and higher performance aredemanded for an operation provided by each of those devices. To satisfysuch a demand, the use of the plurality of laser beams has beenconsidered as one method. For example, simultaneous reading of theplurality of tracks by using the plurality of laser beams easilyincrease the reading speed in an optical disc device. Thus, thedevelopment of an LD, or a multi-beam laser, is demanded which caninject the plurality of laser beams simultaneously.

FIGS. 1 and 2 show the disassembled construction of a conventional.multi-beam laser. FIG. 1 shows a multi-beam laser with two laser beams.FIG. 2 shows a multi-beam laser with four laser beams. These multi-beamlaser have the plurality of laser oscillators 110 on the same substrate111. Each of those electrode 117 is electrically connected to eachcontact electrode 131 formed on a base 132 with each wiring 133 inbetween, respectively. Increase in the number of laser beams requiresnarrower space between each laser beam. For example, suppose the spacebetween two laser beams is 60 μm. Then, if the number of laser beams arefour, the space between each laser beam will be 20 μm. In this way, asthe number of laser beams increases, the space S₁ between each laseroscillator 110 becomes narrower.

SUMMARY OF THE INVENTION

However, in a conventional multi-beam laser, each contact electrode 131is connected to the whole surface of each electrode 117 on each laseroscillator 110, respectively. For that reason, when the number of thelaser beams increases and the space S₁ between each laser oscillator 110becomes narrower, extremely highly precise position matching has beenrequired for those laser beams. That is, since each space between eachelectrode 117 and each contact electrode 131 are close, a smalldisplacement of each contact electrode 131 makes one contact electrode131 connect to the electrode 117 of two laser oscillators 110,respectively. Thus, each laser oscillator 110 can not be drivenindependently. Therefore, if the number of laser beams is increased toachieve more rapidity and higher performance, it causes difficulty inconnecting each contact electrode 131 and each electrode 117 accurately.For that reason, mass production has been also difficult.

The present invention has been realized in view of such problems. It isan object of this invention to provide a photoelectric conversionelement which can keep easy and accurate connection of contact electrodeand a method for manufacturing the same.

The photoelectric conversion element comprises: a photoelectricconversion portion having a semiconductor layer equipped on a substrateand an electrode equipped on the semiconductor layer, a contactelectrode electrically connected to the electrode of the photoelectricconversion portion, and an insulating layer formed between the contactelectrode and the electrode of the photoelectric conversion portion andequipped with an opening for connecting them electrically.

The method for manufacturing the photoelectric conversion elementaccording to this invention includes: forming a photoelectric conversionportion having a semiconductor layer equipped on a substrate and anelectrode equipped on the semiconductor layer, forming an insulatinglayer having an opening for the electrode of the photoelectricconversion portion, and forming a contact electrode electricallyconnected to the electrode of the photoelectric conversion portionthrough the opening of the insulating layer.

In the photoelectric conversion element according to this invention, theelectrode of the photoelectric conversion portion and the contactelectrode are electrically connected through the opening of theinsulating layer. Thus, high precision is not required for the positionmatching of the electrode and the contact electrode, being connectedeasily and accurately.

In the method for manufacturing the photoelectric conversion elementaccording to this invention, the photoelectric conversion portion havingthe semiconductor layer equipped on the substrate and the electrode isformed first. Then, the insulating layer with the opening for thiselectrode is formed. Following that, the contact electrode is formedwhich is electrically connected to the electrode of the photoelectricportion through the opening of this insulating layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a disassembled structure of theconventional multi-beam laser.

FIG. 2 is a perspective view showing a disassembled structure of theother conventional multi-beam laser.

FIG. 3 is a perspective view showing a structure of a laser diode of oneembodiment of the invention.

FIG. 4 is a cross sectional view taken on line I—I of the laser diodeshown in FIG. 3.

FIG. 5 is a perspective view showing the laser diode of FIG. 3 partlydisassembled along the line II—II.

FIG. 6 is a cross sectional view taken on line II—II of the laser diodeshown in FIG. 3.

FIG. 7A, 7B, 7C are a cross sectional view taken on line I—I showingeach manufacturing process of the laser diode of FIG. 3.

FIG. 8A, 8B are a cross sectional view taken on line I—I showing eachmanufacturing process following FIG. 7.

FIG. 9 is a cross sectional view taken on line I—I showing eachmanufacturing process following FIG. 8.

FIG. 10 is a cross sectional view taken on line I—I showing amanufacturing process following FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The embodiments of this invention will be described in detail withreference to the accompanying drawings.

FIG. 3 shows a whole structure of a laser diode that is a photo electricconversion element according to one embodiment of the invention. FIG. 4shows a sectional structure taken on line II—II of FIG. 3. FIG. 5 showsa structure disassembled along the line II—II of FIG. 2. Here, aphotoelectric conversion element refers to an element that convertsoptical energy and electric energy. This photoelectric conversionelement converts optical energy to electric energy and vise versa.

As shown in FIG. 3, this laser diode has the plurality (4 in FIG. 3) oflaser oscillator 10 as a photoelectric conversion portion deployedvertically to the resonator direction A. Each laser oscillator 10 mayhave the same structure each other. As shown in FIG. 4, n-type cladlayer 12, active layer 13, p-type clad layer 14 and cap layer 15 arelaminated successively on one surface, a surface (100), of thesuccessive, same substrate 11. The size of each laser oscillator 10 mayhave the resonator direction A with 350 μm in length and with 12 μm inwidth in the vertical direction. A space S₁ between each laseroscillator 10 is, for example, 3 μm.

A substrate 11 is composed of n-type GaAs with silicon, Si, or selenium,Se, as a n-type impurity for example. Each n-type clad layer 12 iscomposed of n-type AlGaAs mixed crystal with silicon or selenium as an-type impurity, for example. The composition ratio in a class IIIchemical element of this n-type AlGaAs mixed crystal is, for example,45% aluminum, Al, and 55% gallium (%: mole %.) Each active layer 13 iscomposed of, for example, i-AlGaAs mixed crystal without impurities(‘i-’ refers to no impurities.) The composition ratio in a class IIIchemical element of this n-type AlGaAs mixed crystal is, for example,14% aluminum, Al, and 86% gallium. Each p-type clad layer 14 is composedof, for example, p-type AlGaAs mixed crystal with zinc, Zn, as aimpurity. The composition ratio in a class III chemical element of thisp-type AlGaAs mixed crystal is, for example, 45% aluminum and 55%gallium. Each cap layer 15 is composed of, for example, p-type AlGaAsmixed crystal with zinc as a p-type impurity.

Each p-type clad layer 14 has current block layers 16 inserted in bothsides along the resonator direction A which is vertical to the surfaceof paper in FIG. 4 in part of the laminated layer direction. That is,each p-type clad layer 14 becomes narrower in width in the resonatordirection A and in the vertical direction constructing a currentnarrowing portion. Each of these current block layers 16 is composed of,for example, n-type GaAs with silicon or selenium as a n-type impurity.

Each laser oscillator 10 also has each p-side electrode 17 at theopposite side of the p-type clad layer 14 of each cap layer 15,respectively, while the other surface opposing to one surface of thesubstrate 11 has an n-side electrode 18, respectively. Each p-sideelectrode 17 has an alloy composition made by laminating a titanium (Ti)layer, a platinum (Pt) layer and a gold (Au) layer, for example,successively from the side of the cap layer 15 and heat is added thereonto be connected electrically to each cap layer 15. An n-side electrode18 has an alloy composition made by laminating an alloy layer consistingof gold and germanium (Ge),a nickel (Ni) layer, and a gold (Au) layer,for example, successively from the side of the substrate 11 and heat isadded thereon to be connected electrically to the substrate 11.

Furthermore, each laser oscillator 10, as shown in FIG. 3, has a pair offacing films 19 a and 19 b, respectively, which are placed successivelyeach other on a pair of sides vertical to the resonator direction A. Onefacing film 19 a is composed of oxide aluminum (Al₂O₃), for example, andhas a low reflection factor. Another facing film 19 b is composed bylaminating an oxide aluminum layer and an amorphous silicon layeralternately, for example, and has a high reflection factor. In otherwords, light occurred in each active layer 13 is amplified by travelingbetween a pair of facing films 19 a and 19 b to be injected as a laserbeam from the facing film 19 a respectively.

As shown in FIG. 5, a mutually successive insulating layer 20 which iscomposed of an insulating material such as nitriding silicon (Si₃N₄) isformed so as to cover each p-side electrode 17 on each laser oscillator10. That is, this insulating layer 20 covers a pair of sides parallelwith the resonator direction A of each of the laser oscillator 10, i.e.sides of each semiconductor layer and each p-side electrode 17, and thesurface between each laser oscillator 10, respectively. The thickness ofthis insulating layer 20 is , for example, 0.15 μm and has the pluralityof openings 21 corresponding to each p-side electrode 17. Each opening21 exposes about half of one side in the resonator direction A amongeach p-side electrode 17 and is placed alternately not to be side byside in the arrangement direction B which is vertical to the resonatordirection A between each laser oscillator 10 mutually placed side byside.

Now, the position relationship of each opening 21 will be describedfurther by making reference to FIG. 6. FIG. 6 shows a sectionalstructure near a laser oscillator 10 taken on line II—II of FIG. 4. Forexample, on the surface parallel to the substrate 11 each area isdivided in a grid by each line X drawn between each laser oscillator 10in parallel with the resonator direction A and by each line Y drawn inthe center of each laser oscillator 10 vertically to the resonatordirection A. Each opening 21 is placed within each area which aligns ina slanting direction or aligns longitudinally or laterally with morethan one area of space between the areas the openings are positioned. Inother words, each opening 21 corresponding to each laser oscillator 10placed side by side is placed within each area placed in a mutuallyslanting direction. Thus, as the space S₂ between each opening 21 placedside by side in the alignment direction B has one laser oscillator 10between each other, the space S₂is opened wide enough as much as about18 μm. Also, the space S₃ between each opening 21 in the resonatordirection A is opened widely enough as much as about 18 μm in view of adisplacement while manufacturing.

As shown in FIG. 5, each of the contact electrode 31 is electricallyconnected to the p-side electrode 17 in each laser oscillator 10 througheach opening 21, respectively. In FIG. 5, broken lines indicate eachposition where the insulating layer is in a contact with each contactelectrode 31, and dotted areas indicate each position where each opening21 is in a contact with. Thus, each contact electrode 31 extends fromthe center of laser oscillator 10 to the outside in parallel with thealignment direction B corresponding to each opening 21, respectively. Inother words, each contact electrode 31 corresponding to each laseroscillator 10 placed in one side off the center of the alignmentdirection B is extended toward the one side while each contact electrodecorresponding to each laser oscillator 10 in the other side is extendedtoward the other side. It is preferable to form each contact electrode31 by extending from the position corresponding to each opening 21because it widens a contact area with a wire 33 and lowers itsresistance. The space S₄ between each contact electrode 31 in thealignment direction B and the space S₅ in the resonator direction A areopened widely enough, respectively, matching each position of theopenings 21.

Each contact electrode 31 is formed on one surface of a base substrate32 through each wire 33 and constructed by sequentially laminating aplatinum layer and a soldered layer (an alloy layer of Pb and Sn), forexample from the side of the base 32. The base 32 is constructed byaluminum nitride (AIN), for example. Each wire 33 is constructed bysequentially laminating a titan layer, a platinum layer and a gold layerfrom the side of the base substrate 32. An insulating film 34 consistsof aluminum nitride is formed on the surface of each wiring 33 except onwire pad 33 a, for connecting wires.

As is shown in FIG. 5, the semiconductor laser according to thisembodiment is further equipped with a position matching portion 40 forconnecting each p-side electrode 17 and each contact electrode 31 oneach laser oscillator 10. The position matching portion 40 has twosubstrate side position matching portions 41 formed on one surface ofthe substrate 11 and two base substrate side position matching portion42 formed on one surface of the base substrate 32.

Each substrate side position matching portion 41 has a form ofprotrusion with extended parallely with the resonator direction A and isplaced to catch each laser oscillator 10, respectively. Each substrateside position matching 41 has almost the same internal construction asthe one of each laser oscillator 10 except that a current block layes isequipped all over in the p-type clad layer, and each surface isconstructed by the insulating film 20, respectively. In other words, theopposite side of substrate 11 according to each of the substrate sideposition matching portion 41 is fixed in a contact with each contactelectrode 31, respectively. Thus, the substrate side position matchingportion 41 can support the connection of each p-side electrode 17 andeach contact electrode 31 on each laser oscillator 10 and, furthermore,support each laser oscillator 10 supplementary. Also, the insulatingfilm 20 constructing the surface of each side position matching portion41 has each opening 22 on at least a part of the opposing surface toeach contact electrode 31. By jointing each p-side electrode 17 as ametallic layer formed inside of each substrate side position matchingportion 41 with each contact electrode 31, respectively, the junction ofeach laser oscillator 10 and each contact electrode 31 can be supportedmore strongly.

Each base substrate side position matching portion 42 is constructedwith two dents formed by rectangularly removing part of sides of thecontact electrode 31 and the wiring 33, respectively, corresponding toeach substrate side position matching portion 41.

A semiconductor laser with such a construction is manufactured byfollowing.

From FIG. 7A˜7C to FIG. 8A, 8B show each manufacturing process. Eachdrawings are section views taken on line I—I of FIG. 3. First, as shownin FIG. 7 A, prepare the substrate 11 consisting of n-type GaAs mixcrystal, for example. By following the method of Metal Organic ChemicalVapor Deposition, MOCVD, raise the n-type clad layer 12 consisting ofn-type AlGaAs mix crystal, the active layer 13 consisting of I-AlGaAsmix crystal and the p-type clad layer 14 consisting of I-AlGaAs mixcrystal sequentially on the side of one surface (100 surface) of thesubstrate 11.

Next, as shown in FIG. 7B, by following the MOCVD method, for example,raise the current block layer 16 consisting of n-type GaAs on the p-typeclad layer 14. Then, by following the Reactive Ion Etching, RIE, method,for example, remove this current block layer 16 selectively according toa laser oscillator forming area 51 to shape it in a predetermined form.Though the plurality of semiconductor laser forming areas exist on onesurface of the substrate 11, only one semiconductor laser forming areais shown in each flow diagram shown in FIGS. 7-9.

As shown in FIG. 7C, after shaping the current block layer 16, byfollowing the MOCVD method, for example, raise a part of the p-type cladlayer 14 consisting of p-type Al GaAs mix crystal and the cap layer 15consisting of p-type GaAs sequentially on the current block layer 16 andp-type clad layer 14. Then, in order to achieve ohmic contact betweenthe cap layer 15 and the p-side electrode 17 thereon, diffuse zinc intothe cap layer 15.

After diffusing zinc, as shown in FIG. 8A, apply and form a photo-resistfilm 52 on the cap layer 15 to form each opening 52 a and 52 bcorresponding to each laser oscillator forming area 51 and each positionmatching portion forming area 53. Then, evaporate a titan layer, aplatinum layer and a gold layer, for example, on to the photo-resistfilm 52 and the cap layer 15 sequentially to form the p-side electrode17. Next, remove the p-side electrode 17 formed on the photo-resist film52 along with the photo-resist film 52. Thus, each p-side electrode 17remains in order to correspond to only each laser oscillator formingarea 51 and each position matching portion forming area 53,respectively.

After respectively forming each p-side electrode 17, as shown in FIG.8B, by following the RIE method, remove selectively part of the caplayer 15, the p-type clad layer 14, the current block layer 16, theactive layer 13 and the n-type clad layer 12, respectively using eachp-side electrode 17 as a mask. Accordingly the active layer 13, thep-type clad layer 14, and the cap layer 15 are separated respectivelyaccording to each laser oscillator forming area 51 and each positionmatching portion forming area 53. This separation is done using eachp-side electrode 17 as a mask directly, so a lithography process is notrequired and precise separation can be achieved with fewer process.However, without using each p-side electrode 17 as a mask, it ispossible to form a resist film on each p-side electrode 17 through alithography process selectively and etch the resist film used as a maskby following the RIE method to separate them.

After separating them, as shown in FIG. 9A, by following the ChemicalVapor Deposition, CVD, method, for example, form the insulating layer 20on the whole surface of one side of the substrate 11 including thep-side electrode 17. Then, remove the insulating film 20 selectively byetching to form each opening 21 corresponding to each laser oscillatorforming area 51, while forming each opening 22 corresponding to eachposition matching portion forming area, 53, respectively. Be sure toform them within each area that is divided in a grid and aligned in aslanting direction or aligns longitudinally or laterally with more thanone area of space between the areas each opening is formed. In FIG. 9A,each opening 22 is not shown in the section view, so the position in thesectional direction is shown in broken lines. Each opening 21 not shownin the sectional view is also shown in broken lines.

After forming each opening 21 and 22 on the insulating layer 20,respectively, wrap the other surface side of the substrate 11 so thatthe thickness of the substrate 11 becomes 100 μm. This permits easycleaver of the substrate 11, which is done in a process described later.After wrapping the substrate 11, as shown in FIG. 9B, evaporate an alloylayer of gold and germanium, a nickel layer and a gold layer onto theother surface side of the substrate 11 to form an n-side electrode 18.Then, apply heat processing to alloy each p-side electrode 17 and n-sideelectrode 18, respectively.

After applying heat processing, though it is not shown in figures,cleavage the substrate 11 making correspondence to one semiconductorlaser forming area in the resonator direction A and in the verticaldirection, respectively. Then, form an edge face film 19 a and 19 b fora pair of sides perpendicular to the resonator direction A according to, for example, the CVD method, respectively.

Furthermore, though it is not shown, aside from each laser oscillator10, prepare the base substrate 32 consisting of aluminum nitride, forexample. Selectively evaporate a titan layer, a platinum layer and goldlayer sequentially on to the one surface side to form each wiring 33,respectively, making correspondence to each opening 21 of the insulatinglayer 20. At that time, form each wiring 33 so as to by extend towardthe outside of each oscillator in parallel with the alignment directionB from the position corresponding to each opening 20, respectively.Also, form each base substrate position matching portion 42 consistingof rectangularly dented portion corresponding to each substrate sideposition matching portion 41 on part of the side of each wiring 33,respectively.

Next, sequentially evaporate a platinum layer and a soldered layer ontoeach wiring 33, selectively, to form each contact electrode 31 makingcorrespondence to each opening 21 of the insulating layer 20,respectively. At that time, form each contact electrode 31 so as toextend toward the outside of each oscillator in parallel with thealignment direction B from the position corresponding to each opening20, respectively. Also, form each base position matching portion 42consisting of rectangularly dented portion corresponding to each wiring33 that matches to each substrate side position matching portion 41 onpart of the side of each contact electrode 31, respectively. Then,according to CVD method for example, form the insulating film consistingof aluminum nitride on each wiring 33 except on wire pad 33 a,respectively.

Thus, after forming each laser oscillator 10 and each contact electrode31, respectively, as shown in FIG. 10, make each oscillator 10 contactwith each contact electrode 31. At that time, match each base sideposition matching portion 42 formed on base 32 and each substrate sideposition matching portion 41 each other. Hereby, easy and accurateposition matching, is performed.

Then, apply heat processing and connect each contact electrode 31 andeach p-side electrode 17 of each laser oscillator 10 electricallythrough each opening 21 on the insulating film 20 formed between them.Here, the space S₂ and S₃ between each opening 21 on the insulatinglayer 20 and the space S₄ and S₅ between each contact electrode 31 areformed widely enough. Therefore, the high accuracy for their positionmatching is not required, and mutually corresponding each p-sideelectrode 17 and each contact electrode 31 can be connected easily andaccurately. Also, heat processing allows each p-side electrode 17 ofeach substrate side position matching portion 41 to be jointed with eachcontact electrode 31 through each opening 22, respectively. Therefore,the joint between each laser oscillator 10 and each contact electrode 31can be supported more strongly. Accordingly, the semiconductor lasershown in FIG. 3 is formed.

The operation of the semiconductor laser manufactured as described abovewill be described in the following.

A predetermined voltage is applied to between each p-side electrode 17and n-side electrode 18 through each contact electrode 31 at the pointof the power-on to each wire pad portion 33 a of each wiring 33 and eachn-side electrode 18 of each laser oscillator 10. This permits currentinjection into each active layer 13 in each laser oscillator 10 andlight emission occurs due to electron-hole recombination, respectively.Those light rays travel between a pair of the edge face films 19 a and19 b to be amplified and rejected from the edge face film 19 a to theoutside. Here, each contact electrode 31 and each p-side electrode 17are connected through each opening 21 of the insulating layer 20,respectively. Also, the space S₂, S₃, S₄ and S₅ between each opening 21and each contact electrode 31 are formed widely enough. So, it does notrequire high accuracy for their positioning, and each of them isconnected easily and accurately. It allows mutually independent drivefor each laser oscillator 10.

According to this embodiment, each contact electrode 31 and each p-sideelectrode 17 are connected through each opening 21 of the insulatinglayer 20, respectively. While, each opening 21 is placed within eacharea of the gird-divided area on the surface parallel to the substrate11 which aligns in a slanting direction or aligns longitudinally orlaterally with more than one area of space in between the areas eachopening is positioned. Therefore, it does not require highly accurateposition matching between each contact electrode 31 and each p-sideelectrode 17. Accordingly, it does not require high accuracy for theirpositioning, and each of them is connected easily and accurately. Itallows mutually independent drive of each oscillator 10 and massproduction of the laser diode.

According to this embodiment, the substrate side position matchingportion 41 is equipped on the substrate 11, while the base side positionmatching portion 42 is equipped on the base 32, corresponding to thesubstrate side position matching portion 41. By using the substrate sideposition matching portion 41 and the base side position matching portion42, the position of each contact electrode 31 and each laser oscillator10 are matched easily and accurately. Thus, each of contact electrodes31 and p-side electrodes 17 are connected easily and accurately.

Furthermore, according to this embodiment, each substrate side positionmatching portion 41 is protruded and fixed to each contact electrode 31.Thus, it can support the junction of each laser oscillator 10 and eachcontact electrode 31, and, furthermore, support each laser oscillator10.

In addition, according to this embodiment, each substrate side positionmatching portion 41 is constructed almost as same construction as eachlaser oscillator 10 to form each p-side electrode 17, while each opening22 is formed to be opposed to each contact electrode 31 on theinsulating film 20. The joint between each p-side electrode 17 of eachsubstrate side position matching portion 41 and each contact electrode31 allows stronger joint between each laser oscillator 10 and eachcontact electrode 31.

Still further, according to the manufacturing method of thesemiconductor laser according to this embodiment, when separating theactive layer 13, the p-type clad layer 14, the cap layer 15 and the likeaccumulated on the substrate 11 according to each laser oscillatorforming area 51, each p-side electrode 17 is etched as a mask. Thispermits highly accurate separation with less process and achievessimpler manufacturing steps and lower manufacturing costs. Also, iteliminates displacement between each p-side electrode 17 and each caplayer 15. This enhance accuracy of position matching between eachcontact electrode 31 and each laser oscillator 10. Thus, each contactelectrode 31 and each p-side electrode 17 can be connected accurately.

While the present invention has been described in connection with thepreferred embodiment thereof, it will be understood that it is notintended to limit the invention to that embodiment and can be modifieddifferently. For example, the embodiment specifically describes asemiconductor laser with four laser oscillators 10 on the same substrate11. However, the present invention can be applicable widely irrespectiveof the number of the laser oscillator 10.

Also, in the preferred embodiment, the position of each opening 21 onthe insulating film 20 is determined depending on each area divided in agrid by each line X drawn between each laser oscillator 10 in-parallelwith the resonator direction A on the surface parallel with thesubstrate 11 and by each line Y drawn vertically to the resonatordirection A in the center of each laser oscillator 10. However, thenumber of line Y drawn vertically to the resonator direction A can beplural depending on the number of laser oscillator 10.

In other words, each opening 21 can be formed within each of the areasdivided in a grid which aligns in a slanting direction or alignslongitudinally or laterally with more than one area of space in betweenthe areas each opening is positioned, in accordance with each of thelaser oscillator 10 irrespective of the number of the laser oscillator10. To be more specific, each opening 21 corresponding to each laseroscillator 10 placed side by side must be placed within each area placedin a slanting direction mutually among each area divided in a grid. Theslanting direction refers to a direction other than longitudinal andlateral directions, and angle is not related.

In addition, although in the above-mentioned embodiment, each of contactelectrodes 31 is extended respectively in parallel with the alignmentdirection B corresponding to each of the openings 21, the extention maybe done vertical to the alignment direction B. Furthermore, each ofcontact electrodoes may be fromed according to the form of each of theopenings 21.

In addition, in the above-mentioned embodiment, successive insulatinglayers 20 are formed between each p-side electrode 17 and each contactelectrode 31. However, each of insulating layers 20 may be formedseparately between each p-side electrode 17 and each contact electrode31 making correspondence with each p-side electrode 17.

Furthermore, in the above-mentioned embodiment, materials composing eachlaser oscillator 10 are described specifically with examples. However,it is also applicable when each laser oscillator 10 is composed of othermaterials. For example, the embodiment is also applicable to the cladlayer composed of InP and the active layer composed of InGaAs.Alternatively, it is also applicable to each clad layer composed ofAlGaInP and the active layer composed of GaInP.

Still further, the above-mentioned embodiment describes the constructionof each laser oscillator 10 by referring one example. However, eachlaser oscillator 10 having other constructions may also be applied inthe same manner. For example, it is applicable to the one with a guidelayer or the one with a substrate on which a p-type clad layer, anactive layer and an n-type clad layer are laminated sequentially.Therefore, although the p-side electrode 17 is connected to the contactelectrode 31 in the above-mentioned embodiment, the present invention isalso applicable in the same manner when a contact electrode is connectedto an n-side electrode.

Also, the preferred embodiment describes the case in which each p-sideelectrode 17 of each laser oscillator 10 is connected to each contactelectrode 31 formed on the base substrate 32. However, the presentinvention is also applicable to the one in which each semiconductorlayer, each electrode and each contact electrode are laminatedsequentially on a substrate.

Still further, the above-mentioned embodiment specifically describes thesemiconductor laser with laser oscillator 10 as a photoelectricconversion portion. However, the present invention is widely applicableto a photoelectric conversion element with other photoelectricconversion portion which converts photo energy to electric energy orvise versa. For example, it is applicable to other semiconductor lightemitting elements such as light emitting diode, LED or semiconductorlight receptive element such as a photo-detector.

In addition, the above-mentioned embodiment specifically describes thecase in which the MOCVD method is used for laminating a semiconductorlayers on the substrate 11. However, other method such as the MolecularBeam Epitaxy; MBE, method can be used. Furthermore, although thepreferred embodiment specifically described the case in which the RIEmethod is used for selectively removing a semiconductor layer withp-side electrode 17 as a mask, other dry etching or wet etching can beused.

As described above, according to a photoelectric conversion element andthe method of manufacturing the same according to the invention, aninsulating layer is equipped between an electrode of a photoelectricportion and a contact electrode, and, the electrode and the contactelectrode are connected electrically through the opening. Thus, highlyaccurate position matching is not required between the electrode of thephotoelectric conversion portion and the contact electrode, and they canbe connected easily and accurately. Furthermore, mass production of thelaser diode will be possible.

Particularly, according to the other photoelectric conversion elementand the method of manufacturing the same, a position matching portion isprovided for connecting the electrode of the photoelectric conversionportion and the contact electrode. By using the position matchingportion, the position of the electrode of the photoelectric conversionportion and the contact electrode can be matched easily and accuratelyso that they can be connected easily and accurately.

In addition, according to the other photoelectric conversion element andthe method of manufacturing the same, a part of a substrate sideposition matching portion is fixed to the contact electrode. Thus,connection between a laser oscillator and the contact electrode issupplemented and, furthermore, the laser oscillator can be supportedsupplementary.

Also, according to the other photoelectric conversion element and themethod of manufacturing the same, as a metallic layer is formed on thesubstrate side position matching portion, by connecting the metalliclayer and the contact electrode, the connection between laser oscillatorand the contact electrode can be supported more strongly.

According to the other method of manufacturing a photoelectricconversion element, after a semiconductor layer is equipped with anelectrode, it is removed selectively by using the electrode as a mask sothat the photoelectric conversion portion can be formed accuratelythrough fewer process. Accordingly simpler manufacturing processes and adecrease in the production cost can be achieved. Also, it enhances theaccuracy of position matching between the photoelectric conversionportion and the contact electrode, and also the electrode and thecontact electrode can be connected accurately.

What is claimed is:
 1. A method of manufacturing a photoelectric elementcomprising the steps of: forming a photoelectric conversion portionhaving a semiconductor layer equipped on a substrate and an electrodeequipped on the semiconductor layer; forming an insulating layer havingan opening for the electrode of the photoelectric conversion portion;forming a contact electrode electrically connected to the electrode ofthe photoelectric conversion portion through the opening of theinsulating layer; forming the electrode on the semiconductor layer; andremoving the semiconductor layer selectively by using the electrode as amask.
 2. A method for manufacturing a photoelectric conversion element,comprising the steps of: forming a photoelectric conversion portionhaving a semiconductor layer equipped on a substrate and an electrodeequipped on the semiconductor layer; forming an insulating layer havingan opening for the electrode of the photoelectric conversion portion;forming a contact electrode electrically connected to the electrode ofthe photoelectric conversion portion through the opening of theinsulating layer; forming a plurality of the photoelectric conversionportion on the same substrate; forming a plurality of openings at theinsulating layer corresponding to each photoelectric conversion portion,wherein the each opening is positioned within each area which aligns ina slanting direction or aligns longitudinally or laterally with morethan one area of space in between the areas the openings are positioned,and forming a plurality of contact electrodes, respectively,corresponding to each photoelectric conversion portion.
 3. A method formanufacturing a photoelectric conversion element comprising steps of:forming a photoelectric conversion portion having a semiconductor layerequipped on a substrate and an electrode equipped on the semiconductorlayer; forming an insulating layer having an opening for the electrodeof the photoelectric conversion portion; forming a contact electrodeelectrically connected to the electrode of the photoelectric conversionportion through the opening of the insulating layer; forming a positionmatching portion for connecting an electrode of the photoelectricconversion portion and the contact electrode; and connecting the contactelectrode to the electrode of the photoelectric conversion portionelectrically by using the position matching portion.
 4. A method formanufacturing a photoelectric conversion element comprising the stepsof: forming a photoelectric conversion portion having a semiconductorlayer equipped on a substrate and an electrode equipped on thesemiconductor layer; forming an insulating layer having an opening forthe electrode of the photoelectric conversion portion; forming a contactelectrode electrically connected to the electrode of the photoelectricconversion portion through the opening of the insulating layer; forminga substrate side position matching portion having a metallic layer; andconnecting the metallic layer to the contact electrode.
 5. A method formanufacturing a photoelectric conversion element comprising the stepsof: forming a photoelectric conversion portion having a semiconductorlayer equipped on a substrate and an electrode equipped on thesemiconductor layer; forming an insulating layer having an opening forthe electrode of the photoelectric conversion portion; and forming acontact electrode electrically connected to the electrode of thephotoelectric conversion portion through the opening of the insulatinglayer; forming the contact electrode on a base, and connecting thecontact electrode to the electrode of the photoelectric conversionportion electrically.
 6. A method of manufacturing a photoelectricelement, comprising the steps of: forming a photoelectric conversionportion having a semiconductor layer equipped on a substrate and anelectrode equipped on the semiconductor layer; forming an insulatinglayer having an opening for the electrode of the photoelectricconversion portion; forming a contact electrode electrically connectedto the electrode of the photoelectric conversion portion through theopening of the insulating layer; forming the electrode on thesemiconductor layer; removing the semiconductor layer selectively byusing the electrode as a mask; forming a plurality of the photoelectricconversion portion on the same substrate; forming a plurality ofopenings at the insulating layer corresponding to each photoelectricconversion portion, wherein the each opening is positioned within eacharea which aligns in a slanting direction or aligns longitudinally orlaterally with more than one area of space in between the areas theopenings are positioned; forming a plurality of contact electrodes,respectively, corresponding to each photoelectric conversion portion;forming a position matching portion for connecting the electrode of thephotoelectric conversion portion and the contact electrode; connectingthe contact electrode to the electrode of the photoelectric conversionportion electrically by using the position matching portion; forming asubstrate side position matching portion having a metallic layer;connecting the metallic layer to the contact electrode; forming thecontact electrode on a base; and connecting the contact electrode to theelectrode of the photoelectric conversion portion electrically.
 7. Themethod of manufacturing the photoelectric element of claim 1, comprisingthe steps of: forming a position matching portion for connecting anelectrode of the photoelectric conversion portion and the contactelectrode; connecting the contact electrode to the electrode of thephotoelectric conversion portion electrically by using the positionmatching portion; forming a plurality of the photoelectric conversionportion on the same substrate; forming a plurality of openings at theinsulating layer corresponding to each photoelectric conversion portion,wherein the each opening is positioned within each area which aligns ina slanting direction or aligns longitudinally or laterally with morethan one area of space in between the areas the openings are positioned,and forming a plurality of contact electrodes, respectively,corresponding to each photoelectric conversion portion.
 8. The method ofmanufacturing the photoelectric element of claim 7, further comprisingthe steps of: forming a substrate side position matching portion havinga metallic layer; connecting the metallic layer to the contactelectrode; forming the contact electrode on a base, and connecting thecontact electrode to an electrode of the photoelectric conversionportion electrically.
 9. The method of manufacturing a photoelectricconversion element of claim 4, further comprising the steps of: forminga position matching portion for connecting an electrode of thephotoelectric conversion portion and the contact electrode; andconnecting the contact electrode to the electrode of the photoelectricconversion portion electrically by using the position matching portion.10. The method of manufacturing a photoelectric conversion element ofclaim 7, further comprising the steps of: forming the substrate sideposition matching portion having a metallic layer, and connecting themetallic layer to the contact electrode.
 11. The method of manufacturinga photoelectric conversion element of claim 7, further comprising thesteps of: forming the contact electrode on a base, and connecting thecontact electrode to the electrode of the photoelectric conversionportion electrically.
 12. The method of manufacturing a photoelectricconversion element of claim 5, further comprising the steps of: forminga position matching portion for connecting an electrode of thephotoelectric conversion portion and the contact electrode; andconnecting the contact electrode to the electrode of the photoelectricconversion portion electrically by using the position matching portion.13. The method of manufacturing a photoelectric conversion element ofclaim 5, further comprising the steps of: forming the substrate sideposition matching portion having a metallic layer, and connecting themetallic layer to the contact electrode.
 14. The method of manufacturinga photoelectric conversion element of claim 4, further comprising thesteps of: forming the contact electrode on a base, and connecting thecontact electrode to the electrode of the photoelectric conversionportion electrically.
 15. The method of manufacturing a photoelectricconversion element of claim 5, further comprising the steps of: formingthe substrate side position matching portion having a metallic layer,and connecting the metallic layer to the contact electrode.